Piston peening machine



Sept. 12, 1939. D. D. ROBERTSON v PISTON PEENING MACHINE Filed Sept. 9,1936 s Sheets-Sheet 1 P 12, 19.39- D. D. ROBERTSON 2,172,411

PI STON PEENING MACHINE Filed Sept. 9, 1936 6 Sheets-Sheet 2 Q i.. N

M \m P W2? wgxomg m 3 p 12, 1939- I D. D. ROB-ERTSON 2,172,411

PISTON PEENING MACHINE Filed Sept. 9, 1956 6 Sheets-Sheet 3 .11 INVENTORSept. 12, 1939. D. D. ROBERTSON 2,172,411

PI STON PEENING MACHINE Filed Sept. 9, 1956 e Shets-Sheet 4 7545 57 2.526 7? 61 INVENTOR Sept. 12, 1939. D. D. ROBERTSON PISTON PEENING MACHINEI Filed Sept. 9, 1936 6 Sheets-Sheet 6 v 126 illllkfi 125.0! 136'flelmar fl. 2 522 23022,

BY W Patented Sept. 12, 1939 UNITED STATES PATENT OFFICE PISTON PEENINGMACHINE Application September 9, 1936, Serial No. 99,950

4 Claims. (01. 78101) The present invention relates to certain new anduseful improvements in piston peening machines, and it relates moreparticularly to an adjustable Work holder constituting part of saidmachine and adapted to be readily adjusted operatively to hold theengine piston which is to be reshaped by said machine in such fashionthat a rapid series of hammer strokes can be applied to the insidesurface of the skirt Wall of said piston, so that said piston skirt maybe conformed to the enginecylinder.

In the accompanying drawings, in which like reference charactersindicate like parts,

Figure 1 represents a perspective view of a piston peening machineembodying the present invention; v

Figure 2 represents a front elevational View of the piston peeningmachine embodying the present invention.

Figure 3 represents a left side elevational view of the same.

Figure 4 represents a right side elevational view of .the same.

Figure 5 represents a top plan view of the same.

Figure 6 represents a section on line 6-6 of Figure 2.

Figure 7 represents a side elevational view of the trip hammermechanism, with some of the outer housing partlybroken away around thetrip. hammer mechanism, to expose to View some of said mechanism andwith part of the pedestal omitted so as to shorten the view.

Figure 8 represents a front elevational view of the trip hammermechanism, with the hammerarin broken away so as to expose to view thetrip mechanism behind the same, and with the anvil shank also brokenaway; shown on a scale somewhat larger than the scale used in Figure '7,and with the lower, generally upright supporting pedestal entirelyomitted from this view.

Figure 9 represents a perspective view of some of the operative elementsof the hammer trip mechanism;

Figure 10 represents a section on line |0|0 of Figure 11;

Figure 11 represents a section on line I of Figure 8;

1 Figure 12' represents a section on line |2|2 of Figure 11;

"Figure 13 represents a side elevational view of the work holder orpiston support on a somewhat enlarged scale;

Figure 14 represents a plan View of the work holder; 1

Figure 15 represents a section on line l5-|5 of Figure 13.

Within any suitable housing or supporting framework, designatedgenerally by the numeral 20, a generally horizontal shaft 2| is suitably5 journalled, as for instance, in the bearings 22 and 23 on the oppositesides of the housing or supporting frame work. The bearings 22 and 23may be of any suitable construction, as .for instance, the split andcapped bearings indicated 10 generally in Figures '7, 8 and 11. On theshaft 2| any suitable pulley 24 is idly mounted, as for instance, thegenerally V-shaped pulley indicated particularly in Figures 8 and 10, soas to rotate freely upon the shaft. Upon the pulley 24 any suitableannular and concentric driving clutch member 25 may be provided, as, forinstance, that indicated more particularly in Figure 10, having the pairof oppositely inclined, conical frictional surfaces 26 and 21.

A driven clutch member 28 is mounted upon the shaft 2| adjacent thedriving clutch member 25, but keyed thereto by means of the key 29 andslidable axially on said shaft 2| and key 29, and having a suitableannular concentric channel 30 in registration with, andin operativejuxtaposition to the driving clutch member 25, and hav-- ingcorresponding conical friction surfaces 3| and 32 adapted for frictionalengagement with the surfaces 26 and 21.

Behind the housing 20, and carried by the table 33, (which alsocarries'the housing 20) any suitable electric motor 34, is mounted, withits axis parallel to the axis of the shaft 2|, and with a V-pulley 35 onthe shaft thereof, in alignment with the pulley 24. A suitable V-belt 36is placed over the motor pulley 35 and clutch pulley 24, so asoperatively to interconnect the same. By running the motor constantlyand then from time to time pressing the driven clutch member 28 intofrictional engagement with the driving clutch member 25 in the directionof the arrow 31, the shaft 2| may be rotated at a predeterminedspeed;-the shaft 2| remaining stationary when the clutch member 28 is inthe retracted position indicated in Figure 10. In the hub-like portion38 of the driven clutch member 28, an annular groove 39 is provided. Apivot bracket 40 is carried inside the frame or housing 20, and to thepivot bracket 40 the L-shaped arm 4| is pivotally secured at 42. Theupwardly extending portion 43 of the L-shaped arm 4| is bifurcated intoa fork-like terminal which straddles the hub 38 and the upper terminalsof which carry the rollers 44 on horizontal trunnions 45. The rollers 44extend freely into the channel 39 and the hub 38 of the driven clutchmember 28, so that the driven clutch member 28 may be rotated freely inrelation to the fork 43, and so that by oscillating the fork 43 aboutthe pivot 42, the driven clutch member 28 may be mounted into and out ofoperative engagement with the driving clutch member 25, in order toimpart rotary motion to the shaft 2|, or to deprive said shaft of suchrotary motion at the will of the operator.

A helical tension spring 46 may be operatively interposed between thefork 43 and a suitable anchorage 41 carried by the housing 20, therebynormally to tend to retract the driven clutch member 28 from the drivingclutch member 25;

A suitable pull rod or operating rod 48 may be linked to the arm 4 I43at the point 49, and may be extended downwardly to a suitable opening 50in the bottom of the housing 20, and down through the supportingpedestal 5|, to a foot.

treadle 52 pivoted at 53, whereby the clutch may be brought intooperative engagement by depressing the treadle 52 with the foot.

' Upon the shaft 2| a trip cam member 54 is fixedly secured by the key55 intermediate the hub thereof and the shaft 2|; the trip cam member 54having one or more circumferentially distributed eccentric rises 56. Inthe particular illustration shown, there are two cam rises 56 indiametrically opposite positions, although "this number may be variedaccording to the speed of the shaft 2| and the frequency of blows orstrokes desired.

Adjacent the trip cam 54 a cone 5'! is mounted on the shaft 2|, freetomove axially thereon,

and either rotationally free with respect to'the shaft or rotationallykeyed thereto. In the particular illustration shown, the cone 51 is freeboth for axial sliding movement on the shaft 2|,

as Well as rotationally free. In the hub portion 58 of the cone 51, anannular groove 59 is lprovided for receiving the inwardly projectingpins 60 of the cone-operating fork 6|. The coneoperating fork 6| is alsopivoted to the pivot bracket 40 at the point 42, and is also generallytoe-shaped, as indicated in Figure 8. An operating rod 62 is suitablylinked'to the fork arm 6| at the point 63, and extends downwardlythrough a suitable opening 64 at the bottom of the housing 20 and downthrough the table 33 and then through the open upper end of the hollowpedestal 5| to a foot treadle 65 pivoted at whereby the cone 5'! may bemoved axially on the 'shaft 2| by foot operation. A helical tension 88.From the hammer arm hub 10, the hammer arm II extends outwardly anddownwardly as indicated in Figures 5 and 4, and the trip arm I?! extendsdownwardly into alignment with the trip .cam 54 and cone 51.

The hammer arm II and trip arm' I2 have been placed in'generally thesame vertical plane, although these two members may be spaced from eachother in' an axial direction any suitable distance upon the same hub orupon a connecting shaft through which they may be fixedlyinterconnected.

7 To the trip arm I2,a cam follower'shoe I3 is secured, as for instanceby means of screws I4. The cam follower shoe I3 is provided with a fiatarrow I6. The shoe I3 is also provided with an 5 inclined toe 11, havingsubstantially the same inclination as the surface of the cone 5! and inoperative juxtaposition to said cone, whereby the contact between saidtoe "I1 and cone 51 will establish the limiting position of the trip arm10 I2, and hence of the hammer arm II on the operative stroke.

A helical tension spring I8, or any other suitable spring such as a leafspring, cantilever type or beam type, may be operatively interposed be-15 tween the trip arm I2 or the hammer arm H at some stationary part ofthe frame work or housing. In the 1 particular illustration shown, the

helical tensionspring is interposed between the anchorage 'IS on thetrip arm'and an adjustable 20 anchorage adjustably carried in the backwall w 8 I of the frame work or housing. The adjustable anchorage 80 isin the form of a screw which is extended freely through an opening 82 inthe by thenut 83 journaled in the outer enlarged opening 84 in thehousing wall and having an exf ternal knurled or other suitable enlargedflange or ring 85 for manual engagement in order to tighten or loosenthe spring I8.

screw anchorage 80 may also be provided with a longitudinal key-way 86,into which the smooth reduced end 81 ofa set-screw 88 is adapted toproject, so as to prevent the screw anchorage 80 "housing wall 8| and isscrew-threadedly engaged 25 The adjustable glo from turning as the nut83 is rotated thereon-$5 Ihe nut 83 may also be provided with a Slightannular groove 89 through which a tangential pin 90 may be extendedthrough that'portion of the housing so as to lock the nut 83 axiallyterfering with its rotation.

If desired, additional means'may be provided for limiting the hammeringmotion of the hammer II, as for instance the set-screw 9|, screwin theenlarged opening 84, without however ill-{40 threadedly extended throughthe portion 92 01 ,55

the housing, as indicated at 93, and having its inner-most end 94 inalignment with the triparm I2, so as to act as a stop for said trip-armand also for the hammerarm II. The outer end of the screw 9| may beprovided with a knurledam head 95, so that it'may be manually adjusted,and may also, be provided with a knurled or other suitable lock nut 96,whereby it may be locked in any adjustable position, as indicatedparticularl in Figure 11. I r I To the basal portion 91 of the housing20, the anvil holder 98 is suitably. secured as, for instance, by thebolts 99. p p

The anvil holder 98 is provided with the bottom and top flat guidesurfaces I00 and IOI, on the- ,8 0

laterally projecting portions I02 and "I03 respec-- tively, carried bythe upright portion I04. The surfaces I00 and IOI are parallel with eachother and between 'them a slide I05 is adjustably mounted, as indicatedin Figures 8, lland 12. A 65 loose clamping plate I06 is disposedbetween the laterally projecting portions I02 and I03 and serves as thefourth side of a moreor less fully enclosed guide passageway for theslide I05. The

an outwardly projecting boss I08 for reinforcing sa d wall andincreasing the length of the screwthreaded hole, and a bolt I09 isextended through a corresponding and registering opening H0 in g theclamping plate I06 of the anvil holder and is threaded into the wall I04so as to permit the tightening of the plate I06 against the slide I05,thereby to lock the slide in any predetermined position. The slide I05is in turn provided with an elongated opening or slot I I I which clearsthe bolt I09, so that the bolt may extend through the slide without itinterfering with the movement thereof within the necessary limits ofsuch movements. The anvil holder mayalso be provided with anotherlaterally projecting portion II2 extending from the upright or verticalwall I04 or from the clamping plate I06, through which an adjustmentscrew H3 is screw-threadedly extended and the inner end of which bearsagainst the lower end II4 of the slide I05. A knurled head II 5 isprovided on the screw II3 so as to facilitate its manual operation.

The adjustment of the anvil slide I05 in relation to the hammer arm IIor in relation to the hammer point I I6 thereof involves the temporaryloosening of the bolt I09 and the adjustment of the screw II3 to thedesired point and then the subsequent tightening of the bolt I09 again.In order to afford access to the head N1 of the bolt I09 with a suitablesocket Wrench, a registering opening II8 may be provided in the sidewall II9 of the housing 20. The upper end of the anvil slide I05 carriesan anvil table I preferably formed integrally therewith and generally ata right angle thereto and the anvil table is recessed slightly at apoint in registration with the hammer point II6 as indicated at I2I andinto said recess a small anvil plate I 22 is inserted, held in placeagainst lateral displacement by suitable screws I23. The anvil plate I22may be of a specially hard metal or a specially tough metal, as forinstance, some special grade of tool steel or other suitable steel oralloyed steel, while the anvil table I20 and slide I05 may be made of asteel forging or the like.

At the lower end of the anvil table I20, a pair of similar arms I24 andI25 may be pivotally mounted about the pivot I21.

At the upper end of the anvil table I20, another pair of pivot armsI24-a and I25a may be pivotally mounted about the pivot I25.

The juxtaposed upper and lower arms I24 and I24a may be interconnectedwith a connecting rod I28 riveted or otherwise fixedly secured to saidjuxtaposed arms, While the juxtaposed upper and lower arms I25 and I25-amay be similarly interconnected by the rod I29 similarly secured theretoso that the swinging or pivotal motion of the juxtaposed arms at the topand bottom will be in unison or simultaneous. The free ends I30, I30a,I3I and I3Ia of the upper and lower arms may be also further andsimilarly interconnected by or give pivotal bearing totrunnions I32 andI33 whereby the rollers I34 and I35 may be loosely or rotatably mounted.

To the lower projecting portions I36 and I3! of the arms I 24 and I25,the perforated and in ternally threaded nut-like members I38 and I39 arepivotally secured by loose rivets I40 or the like, extending through theright angular base portions MI and I42 thereof. The internal screwthreads in the nut-like members I38 and I39 are threaded in oppositedirections;that is, one being a right-handed thread and the other beinga left-handed thread. The two nut-like members I 38 and I39 areinterconnected by means of a screw stem I43 having oppositely threadedends I44 and I45, corresponding to the internal threads of thecorresponding nut-like members I38 and I39, so that the rotation of thestem I43 in one direction will bring the nut-like members I38 and I39together while the rotation in the 0pposite direction will move themabout, thereby to bring the lower ends of the arms I25 together or tospread them apart as the case may be, and so as oppositely to move theouter roller-carrying ends I30 and I3I. A centering bracket I4! issecured to the lower side of the anvil table I20 by means of screws I48,and the outwardly projecting flange I49 thereof is provided with a slotI50, the opposite sides of which engage and project into a slightannular channel or groove I5I ;-thereby to center the oppositelythreaded stem I43. the stem I 43, as for instance, that indicated at I52may be made of polygonal cross-section as for instance, the squarecross-section indicated in Figure 15, so as to receive the correspondingsocket of a wrench-like key I53 so that the adjustment may be made morereadily.

The pivot I26 may be in the form of a bolt as indicated in Figures 11and 14, having its pivotal portion of slightly larger diameter than theouter diameter of the screw-thread so that the shoulder formed betweenthe pivotal portion and the screw thread will act as a stop intightening up the bolt so that the flat arms pivoted thereon may befree. The pivot I21 may be similarly arranged, although it may beprovided with a nut I54 which may be moved up to the fiat arms I24 and I25 to the desired extent and then locked in place by the lock nut I55.The pivot member I2'I may be further extended into a stem I55 onto wlnchthe end holding arm I51 may be adjustably mounted as indicated inFigures 11 and l4:- being held in any particular place by a set screw I58 having a suitable knurled head. The arm I5! is preferably providedwith a ball-shaped upper contact end I59 which contacts the closed endof the piston designated generally by the numeral IIiIimangil1 indicatedin dotted lines in Figure 11.

e ammer point. IIIS ma al v hard or tough steel and is y so be ofspeclal nto the end of the hammer arm II as indicated in Figure 11. Thishammer point may be eithe screw threadedly inserted or may be insertedinto zfriginhhole of smaller diameter than the head e ammer oint V alateral set scrlwand then held in place by As indicated particularly inFigure 11, the pedestal 5! 1s generally hollow and open at its upper andto the upper flange I 5 is secured by means of the bolts IE table 33 inturn the hammer housing 2 E22 cuXed boy means of the bolts I63. k

sui able sheet metal cover I64 of I tour is then extended over thehousirig z ai v r ll as over the motor 34 behind said housing so as :3551011110180615 enclose all the operative mecha- The height of thepedestal 5I is prefer as to permit the operator to sit in fro t ii f tlimachlne on an ordinary chair with his feet on the foot treadles and withthe anvil more or less approximately at table height so as to permit theoperator to manipulate the piston on the anvil with his hands and alsoto have his eye focussed on the hammering zone inside the piston whilethe operator is in such seated position.

The table 33 is preferably extended laterally on either side of thehammer housing 20 and on either side of the sheet metal casing I64 so asto provide horizontal table areas I65 and I66upon which the work inprogress may be placed.

I24'and.

One of the outer ends of preferably inserted IBI thereof the table wheell 61 may be mounted on one of the ends, as

If desired, an abrasive wheel such as an emery for instance, on theright end of the shaft of the motor 34 or upon a suitable extensionthereof, on which the piston maybe trimmed by grinding if necessary. Theemery or car'borundum or abrasive wheel I61 is of the face-grinding typea as indicated in Figure 7. If desired, the table 33 may be elevatedslightly as at I68 adjacent the face of the abrasive wheel I51 so thatthe piston may be rested thereon for grinding;the upper surface I69being preferably flat and horizontal and at a right angle to the face ofthe abrasive bead-like or ledge portions I12 which keep the work fromsliding oil the table or shelf.

In the sheet metal cover I64, openings H3 and H4 may also beprovided foraccessto the adjustments 85, 95 and H5, and another opening I may alsobe: provided in registration with the openingl l8 for access to the bolthead I ll. Side openings I16 and ill at the base of the pedestal areprovided for the passage of the foot control means heretofore describedin the front wall of the sheet-metal cover 164, a generally verticalopening I18 is providedsufiicient to clear the hammer-arm ll.

The present invention may be embodied in other specific forms withoutdeparting from the spirit .or essential attributes thereof, and it istherefore desired thatthe presentembodiment be'considered in allrespects as illustratiye and not restrictive, reference being had toth'eappended;

claims rather than to the foregoing description to indicate the scope ofthe invention.

Having thus described the invention, what is herebyclaimed as new-anddesired to be secured by Letters Patent, is: i 1. In a piston peeningmachine, an adjustable work'holder including'an'anv'il-block having apair'of arms pivoted at its upper portion and a pair of arms eachpivoted at the lower portion of the anvil-block, a rotatably mountedroll carried by the aligned outer ends of an arm of each pair andadapted to contact and position a piston in operative engagement withthe anvil-block, the

inner ends of at least one pair of said arms extending inwardly beyondthe pivot point of each, and a'manually operable screw connecting saidinner ends together for simultaneously and uniformly adjusting thedistance between. said rolls to adapt the holder'to receive pistons ofdifferent diameters. 7 a

2. In a piston peening machine, an adjustable work holder including ananvil-block having a;

pair of arms pivoted at its upper portion and a pair of arms eachpivoted between its ends at the lower portion of the anvil-block, arotatably mounted roll carried by the aligned outer ends of an arm ofeach pair and adapted to contact and the anvil-block, and a manuallyoperable screw connecting the inner ends of the lower arms together forsimultaneously and uniformly adjusting the distance between said rollsto adapt the holder to receive pistons of different diameters. f

. =15 position a piston in operative engagement with ously and uniformlyadjusting the distance between said rolls to adapt the holder to receivepistons of different diameters. I l

work holder including an anvil-block having a pair of arms. pivoted atits upper portion and a pair of arms each pivoted between its ends at acommon point on the lower: portionof the anvilblock, a rotatably mountedroll carried by the aligned outer ends of an arm of each pair andadapted to contact and position the skirt of a piston inoperative-engagement with the anvil' block, a manually operable screwconnecting the inner ends of the lower arms together for simultaneouslyand uniformly adjusting the distance between said rolls to adapt theholder to receive pistons of different diameters, and an arm mounted onthe lower portion of the anvil-block and having a free end engageablewith the closed end wall of said piston and adjustable longitudinally 3,4. In a piston peening machine, an ad ustable

